1.acid: a solution whose pH is below 7. It has a high concentration of Hydronium ions and a low concentration of Hydroxide ions.

2.atomic mass: the average mass of one atom measured in atomic mass units (amu).

3.atomic number: equal to the number of protons in the atom of an element.

4.base: a solution whose pH is above 7. It has a high concentration of Hydroxide ions and a low concentration of Hydronium ions.

5.buoyancy: a measure of the upward force a fluid exerts on an object.

6.chemical change: a change or reaction where a new substance is produced.

7.chemical symbol: one or two letter abbreviation for the element.

8.cohesion: the tendency of water molecules to stick together.

9.compound: substance made of two or more elements that cannot be separated by physical means. Water is an example of a compound.

10.covalent bond: when two non-metals combine, the share electrons.

11.density: a property that describes the relationship between mass and volume

12.electrolytes: substances that can conduct an electric current when they are dissolved in water.

13.element: substances containing only one kind of matter. Hydrogen in an example of an element.

14.group/family: the vertical columns of the periodic table. These all carry the same number of valence shell electrons.

15.heterogeneous mixture: a mixture in which different samples are not necessarily made up of exactly the same proportions. Vegetable soup is an example since you may get different vegetables in each bite.

16.homogeneous mixture: a mixture that is the same throughout. Lemonade is an example because each sip should taste the same.

17.ionic bond: a bond between a metal and a non-metal in which the force of the attraction holds the ions together.

18.Law of Conservation of Mass: the law that states that mass is neither created, nor destroyed in a chemical reaction.

19.matter: anything that has mass and takes up space.

20.metalloids: those elements who share properties between metals and non-metals.

21.mixture: substance containing more than one kind of matter. Cake batter is an example of a mixture.

22.neutral: a solution whose pH is exactly 7. It has the same Hydroxide and Hydronium ion concentration.

23.physical change: a change that does not altar the chemical composition of a compound.

24.products: the elements/compounds that are formed/broken apart in a chemical reaction. They are found on the right side of the equation.

25.reactants: the elements/compounds that combine/break apart in a chemical reaction. They are found on the left side of the equation. Reactants -> Products

26.saturated solution: a solution that has the maximum amount of a solute dissolved.

27.solubility: how much solute you can dissolve before the solution becomes saturated.

28.solute: the substance in a solution in the smallest amount that is dissolved by the solvent. In a salt water solution the salt is the solute.

29.solution: a homogeneous mixture of a solvent and a solute. Salt water is an example.

30.solvent: the component of a solution that dissolves the solute and is present in the greatest amount. Water is an example.

31.supersaturated solution: a solution that has more than the maximum amount of solute dissolved.

32.unsaturated solution: a solution that has less than the maximum amount of solute dissolved.

33.valence electrons: the electrons in the outermost electron cloud surrounding an atom's nucleus.

34.viscosity: a measure of a material's resistance to flow. Water is less viscous than ketchup.